Real Cars in City is an open-world driving simulator: a city map, a selection of cars, and no particular objective beyond driving around it.
Free-roam driving games work because the city itself is the content — finding a road you haven't taken, or a jump you didn't know was there, is the whole point.
It's a free-roam driving simulator — the city and the cars are the content, rather than a race or campaign structure.
Yes — several vehicles are available and they handle differently enough to change how the map plays.
Yes, though it's a 3D open world — close other tabs on older hardware.